{"record":{"id":"df755c2943fa7775","repo":"xai-org/grok-build","slug":"merge-of-base-ref-base-failed-merge-out","errorCode":null,"errorMessage":"merge of base ref '{base}' failed: {merge_out}","messagePattern":"merge of base ref '(.+?)' failed: (.+?)","errorType":"exception","errorClass":"anyhow::Error","httpStatus":null,"severity":"error","filePath":"crates/codegen/xai-grok-workspace/src/session/git.rs","lineNumber":3077,"sourceCode":"    let (merged, merge_out) =\n        git_cli_raw_mut(git_root, &[\"merge\", \"--no-edit\", \"FETCH_HEAD\"]).await?;\n    if merged {\n        let sha = git_cli(git_root, &[\"rev-parse\", \"HEAD\"]).await?;\n        return Ok(GitSyncBaseResult {\n            outcome: GitSyncBaseOutcome::Merged { sha },\n        });\n    }\n    if merge_in_progress(git_root).await? {\n        let files = git_cli(git_root, &[\"diff\", \"--name-only\", \"--diff-filter=U\"])\n            .await?\n            .lines()\n            .map(str::to_owned)\n            .collect();\n        return Ok(GitSyncBaseResult {\n            outcome: GitSyncBaseOutcome::Conflicts { files },\n        });\n    }\n    anyhow::bail!(\"merge of base ref '{base}' failed: {merge_out}\")\n}\n/// Reject a ref/branch value that could be parsed as a git option (leading `-`)\n/// or that carries whitespace/control characters or `..`. A boundary guard for\n/// client-influenced refs (notably `base_ref`) so they cannot be smuggled in as\n/// flags; combined with `--end-of-options` at each call site.\nfn ensure_ref_arg_safe(value: &str, what: &str) -> Result<()> {\n    anyhow::ensure!(!value.is_empty(), \"{what} must not be empty\");\n    anyhow::ensure!(\n        !value.starts_with('-'),\n        \"{what} '{value}' must not start with '-'\"\n    );\n    anyhow::ensure!(\n        !value.chars().any(|c| c.is_whitespace() || c.is_control()),\n        \"{what} '{value}' contains whitespace or control characters\"\n    );\n    anyhow::ensure!(\n        !value.contains(\"..\"),\n        \"{what} '{value}' must not contain '..'\"","sourceCodeStart":3059,"sourceCodeEnd":3095,"githubUrl":"https://github.com/xai-org/grok-build/blob/bc7f02eddd3d84085849dc19ed216f11c23b0571/crates/codegen/xai-grok-workspace/src/session/git.rs#L3059-L3095","documentation":"In the base-sync merge flow, when `git merge` of the base ref finishes with neither clean success nor a conflict-marker outcome, the code bails with the merge command output. This means git itself failed (not a resolvable conflict) during syncing the base ref.","triggerScenarios":"git merge --ff/merge of base ref returns an unexpected exit code — e.g. unrelated histories with no merge strategy, ref locked, index locked, or corrupt object.","commonSituations":"Index.lock left by a crashed process; base ref naming an unrelated history; .git permissions issues; concurrent git processes in the same worktree.","solutions":["Read merge_out in the message for the concrete git error and fix that (e.g. remove stale .git/index.lock)","Verify the base ref is valid and shares history or pass --allow-unrelated-histories semantics via config the library exposes","Ensure no other git process is running in the worktree","Abort any in-progress merge: `git merge --abort` then retry"],"exampleFix":"// before\nsync_base(git_root, base=\"origin/main\").await?;\n// after\nrm -f .git/index.lock && git merge-base HEAD origin/main # verify related history, then retry","handlingStrategy":"try-catch","validationCode":"let lock = git_root.join(\".git/index.lock\");\nif lock.exists() { anyhow::bail!(\"stale index.lock present; remove before merging\"); }\nlet _ = std::process::Command::new(\"git\").arg(\"-C\").arg(git_root).args([\"merge-base\",\"HEAD\",base]).output()?;","typeGuard":"fn merge_hard_failed(msg: &str) -> bool { msg.starts_with(\"merge of base ref\") && !msg.contains(\"CONFLICT\") }","tryCatchPattern":"match sync_base(git_root, base).await {\n    Ok(r) => handle_outcome(r),\n    Err(e) if e.to_string().contains(\"merge of base ref\") => {\n        let _ = git_cli(git_root, &[\"merge\",\"--abort\"]).await; // then fix per merge_out and retry\n        return Err(e);\n    }\n    Err(e) => return Err(e),\n}","preventionTips":["Clear stale .git/index.lock after crashes before merging","Ensure the base ref shares history with HEAD","Serialize git operations per worktree to avoid contention","Run git fsck if object corruption is suspected"],"tags":["git","merge","subprocess"],"backgroundTag":"git-merge-failed","analyzedSha":"bc7f02eddd3d84085849dc19ed216f11c23b0571","analyzedAt":"2026-08-31T04:59:42.031Z","schemaVersion":2},"datasetVersion":"2026-08-31T09:17:48.483Z"}